diff --git a/src/eval.c b/src/eval.c
index d313c5d..0e9ec9e 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -463,6 +463,7 @@
 static void f_append __ARGS((typval_T *argvars, typval_T *rettv));
 static void f_argc __ARGS((typval_T *argvars, typval_T *rettv));
 static void f_argidx __ARGS((typval_T *argvars, typval_T *rettv));
+static void f_arglistid __ARGS((typval_T *argvars, typval_T *rettv));
 static void f_argv __ARGS((typval_T *argvars, typval_T *rettv));
 #ifdef FEAT_FLOAT
 static void f_asin __ARGS((typval_T *argvars, typval_T *rettv));
@@ -7875,6 +7876,7 @@
     {"append",		2, 2, f_append},
     {"argc",		0, 0, f_argc},
     {"argidx",		0, 0, f_argidx},
+    {"arglistid",	0, 2, f_arglistid},
     {"argv",		0, 1, f_argv},
 #ifdef FEAT_FLOAT
     {"asin",		1, 1, f_asin},	/* WJMc */
@@ -8859,6 +8861,41 @@
 }
 
 /*
+ * "arglistid()" function
+ */
+    static void
+f_arglistid(argvars, rettv)
+    typval_T	*argvars UNUSED;
+    typval_T	*rettv;
+{
+    win_T	*wp;
+    tabpage_T	*tp = NULL;
+    long	n;
+
+    rettv->vval.v_number = -1;
+    if (argvars[0].v_type != VAR_UNKNOWN)
+    {
+	if (argvars[1].v_type != VAR_UNKNOWN)
+	{
+	    n = get_tv_number(&argvars[1]);
+	    if (n >= 0)
+		tp = find_tabpage(n);
+	}
+	else
+	    tp = curtab;
+
+	if (tp != NULL)
+	{
+	    wp = find_win_by_nr(&argvars[0], tp);
+	    if (wp != NULL)
+		rettv->vval.v_number = wp->w_alist->id;
+	}
+    }
+    else
+	rettv->vval.v_number = curwin->w_alist->id;
+}
+
+/*
  * "argv(nr)" function
  */
     static void
diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index a7df2c3..04c9a61 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -7211,6 +7211,7 @@
     else
     {
 	curwin->w_alist->al_refcount = 1;
+	curwin->w_alist->id = ++max_alist_id;
 	alist_init(curwin->w_alist);
     }
 }
diff --git a/src/globals.h b/src/globals.h
index 058341b..d831db9 100644
--- a/src/globals.h
+++ b/src/globals.h
@@ -601,6 +601,7 @@
  * to this when the window is using the global argument list.
  */
 EXTERN alist_T	global_alist;	/* global argument list */
+EXTERN int	max_alist_id INIT(= 0);	    /* the previous argument list id */
 EXTERN int	arg_had_last INIT(= FALSE); /* accessed last file in
 					       global_alist */
 
diff --git a/src/main.c b/src/main.c
index c29d6be..9c92f7a 100644
--- a/src/main.c
+++ b/src/main.c
@@ -322,6 +322,7 @@
     init_yank();		/* init yank buffers */
 
     alist_init(&global_alist);	/* Init the argument list to empty. */
+    global_alist.id = 0;
 
     /*
      * Set the default values for the options.
diff --git a/src/structs.h b/src/structs.h
index 16a20716..6f95300 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -675,6 +675,7 @@
 {
     garray_T	al_ga;		/* growarray with the array of file names */
     int		al_refcount;	/* number of windows using this arglist */
+    int		id;		/* id of this arglist */
 } alist_T;
 
 /*
diff --git a/src/version.c b/src/version.c
index 85ab680..b3ec0d3 100644
--- a/src/version.c
+++ b/src/version.c
@@ -735,6 +735,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    312,
+/**/
     311,
 /**/
     310,